So, I went through your old posts to try and figure out a few things. Have you and Michael only been dating since around December?
I guess, the Valentine's thing aside, I'm looking a bit beyond the actual question and wondering what else might be going on. I know you said that Danny had an attraction towards Michael? Has that passed now? Or is it doubly hard for him because he's battling envy *and* jealousy?
If it has only been a few months since you started dating, how fast have you moved? How often have you been seeing Michael? Could it all be a little too fast to reasonably expect Danny to get on board with it? Are you being considerate, patient, supportive, reassuring and loving? Are you ensuring that NRE isn't getting the better of you?
On the other hand, is Danny owning his own issues? When he feels something, can he work out why and come to you for support, rather than a 'fix'?
Finally, something really struck me as the bottom line of all this.
I choose to follow a hierarchical model of poly - nobody is forcing me to do that. For me, it means that I will always put my primary first, because that is what primary means - primary partner, priority person, person I want to be with for the rest of my life, person that means the most to me. That doesn't mean I'm a slave to my primary's every whim - but it does mean that if I'm stuck between a rock and a hard place, I try to think about what will be the best course of action for our future, rather than what I want in the moment.
I do agree that if Michael has chosen to get involved with you, not as a joint primary, but as a secondary, it is going to come with some realistic boundaries and maybe even pitfalls from his perspective. Did you, Danny and Michael ever agree on a dating schedule, or did you sort of drift into seeing Michael as much as you wanted to?
Being the V is hard, so I've been told.... ~grins~ My GF tells me all the time. It's a massive balancing act, for sure. But you can't be responsible for anyone else's feelings - you can only control the way you behave and the way you outline your own expectations.
Anecdote-wise... I am a joint primary to my GF. Her husband is the other primary. She sleeps in their bed most of the time. We agreed pretty early on that she would spend the night with him on Valentine's Day, his birthday, her birthday, Christmas, etc. Those things don't matter to me. I also don't mind if she only spends two nights a week in my bed. I like sleeping with the cats and dogs anyway...
At first, her husband was so upset about her sleeping in my room that he would pace around the house at 4am, coughing and making us aware of his distress. It took about 6 months, but he seems to sleep soundly now. We took it slow, but kept it balanced by making intentions and expectations clear. Perhaps you could have that kind of talk with your guys, if you haven't already? i.e. discuss realistic, measurable scheduling and plans for *how* slow you need to go for Danny? Then outlining and discussing these with Michael?